1 <!DOCTYPE html>
2 <html>
3 <head>
4 <meta charset="utf-8">
5 <title></title>
6 <style>
7 #div1{width: 100px; height: 100px;background-color:red;position: absolute;
8 left: 300px;top: 50px;}
9
10 #div2{width: 1px; height: 300px;background-color:black;position: absolute;
11 left: 100px;top: 0px;}
12 #div3{width: 1px; height: 300px;background-color:black;position: absolute;
13 left: 300px;top: 0px;}
14 </style>
15 <script>
16 var timer=null;
17 function startMove(iTarget){
18 var oDiv=document.getElementById('div1');
19 clearInterval(timer);
20 timer=setInterval(function(){
21 var speed=0;
22 if(oDiv.offsetLeft<iTarget){
23 speed=7;
24 }
25 else{
26 speed=-7;
27 }
28 if(Math.abs(iTarget-oDiv.offsetLeft)<=7){
29 clearInterval(timer);
30
31 oDiv.style.left=iTarget+'px';
32 }
33 else{
34 oDiv.style.left=oDiv.offsetLeft+speed+'px';
35 }
36 },30)
37 }
38 </script>
39 </head>
40 <body>
41 <input type="button" value="到100" onclick="startMove(100)" />
42 <input type="button" value="到300" onclick="startMove(300)" />
43 <div id="div1">
44 </div>
45 <div id="div2">
46 </div>
47 <div id="div3">
48 </div>
49 </body>
50 </html>